The overall goals of this Program Project are to evaluate the cross clade activity of DNA/MVA protocols for immunodeficiency virus vaccines. The overall objectives of this core is to provide the required experimental animals and support services needed to facilitate the AIDS vaccine development efforts of this Program Project. This will include provision of 2-3 year old retrovirus-free (SIV, STLV-1, SRV) rhesus macaques from the Yerkes macaque breeding colonies; immunization of the animals (DNA priming and recombinant MVA boost); daily monitoring of the experimental animals to assess the animals clinical and physical condition and to provide specimens for laboratory evaluations; perform complete blood cell counts (CBCs) and flow cytometry evaluations to determine lymphocyte subsets; and perform complete gross and histologic evaluation of any experimental animals that die during the course of the study. Provision of these resources and support services will facilitate the development and pre-clinical evaluations of AIDS vaccines as proposed in this Program Project.